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Operating Systems, Fall 2007, Homework 10

This homework will be covered in practise session on Thursday 22.11.2007 (week 47).

The exercises are based on chapters 12 and 14. There are no exercises related to Chapter 13. However, you are expected to know the content already from previous courses. If you do not, please study the Chapter 13 also. It will help to understand the Chapter 14.

1. Problem 12.7 from text book [Stal05, p. 577] [Stal01, p. 563]
   

2. What are the biggest differences between Linux ext2fs and Microsoft NTFS file systems as compared to basic techniques given in Ch 12. How do they differ from each other?
   1. disk partitioning ?
   2. file metadata (such as attributes) and its managemenet?
   3. disk block allocation for files?
   4. locating a file from directory tree?
   5. disk system consistency?
   6. size restrictions?
   The course book will not give you answers to all of the questions above, you need to use additional sources. Suitable ones are for example Tanenbaum's book Modern Operating Systems, wikipedia, ... Please collect also the location of each fact, so that you will be able to give references to the original sources.

3. Problem 14.1 from text book [Stal05, p. 640] 13.1. [Stal01, p.605 ]
   

4. RPC (value: 2 questions!)
   Study the rpc mechanisms available in Linux (man rpcgen). You can use the example files: makefile, dice.x, dice_prog.c and dice_caller.c. You need first to compile them. The client can access the remote procedure (server) by giving the name of the node (f.e. melkinkari) as the first parameter in the startup command.

   Modify this example or create a new program. Make a remote procedure factorial, that calculates the factorial (n!) of a given (positive small integer) parameter and returns it to the caller. Make also a test client for your procedure. Please test your program only with small (<30) integer values.

   Why are you not allowed to edit the dice.h file? What is the purpose of the two .c-files the rpcgen generates? Can you read them? Can you find the calling points related to your files from them?

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Tiina.Niklander@cs.helsinki.fi